The Carnegie Corporation was founded in 1911 by Andrew Carnegie to continue his philanthropic work after his death. In 1901 Carnegie offered the City of New York 5.2 million dollars to establish a branch library system. The collection consists of correspondence that chronicles the creation of these circulating libraries. The bulk of the letters dated 1901-1912 were sent to Andrew Carnegie by John Shaw Billings, Director of the New York Public Library. The correspondence discusses the Carnegie gift, cost estimates and specific sites for branches, library needs, and plans to finance ongoing library operations. Other correspondence pertains to branch libraries in Brooklyn and Queens including letters relating to the proposed merger of the Brooklyn Library and the Brooklyn Public Library.